Symmetric boundary element method for "discrete" crack modelling of fracture processes

Giulio Maier; Attilio Frangi

Giulio Maier Technical University of Milan
Attilio Frangi Technical University of Milan

Abstract

Analysis of fracture processes in structures of quasi-brittle concrete-like materials is here discussed on the basis of discrete cohesive crack models and of a nontraditional boundary element method. This method, called "symmetric Galerkin BEM", is characterized by the combined use of static and kinematic sources (i.e. traction and displacement discontinuities) to generate a symmetric integral operator by its spacediscrclization in the Galerkin weighted-residual sense. Consistently, the discrete crack model is enforced in a weak sense and expressed in terms or Prager's generalized variables. On this basis, some of the main aspecls of a computational theory of quasi-brittle fracture mechanies are presented and discussed.

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References

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